First of five Phase-3.2 migration clusters. Foundation utility
classes (NSValue, NSNumber, NSDictionary, NSMutableDictionary, NSSet)
in `library/modules/platform/uikit.sx` move from the explicit
`#objc_call(T)(recv, "selector:", args)` form to declarative
`#foreign #objc_class("Cls") { ... }` blocks with `recv.method(args)`
dispatch.
Classes declared (all near the top of uikit.sx, after the CGRect
struct):
- NSValue → CGRectValue (instance)
- NSNumber → numberWithBool (class), doubleValue +
unsignedLongValue (instance)
- NSDictionary → objectForKey (instance)
- NSMutableDictionary → dictionary (class), setObject_forKey (instance)
- NSSet → anyObject (instance)
Each call site casts the `*void` receiver to the typed foreign-class
pointer before dispatch — the existing `*void` shape is preserved
in the struct fields and outer parameter types; only the dispatch-
local copy is typed. This keeps the diff scoped to call-site
rewrites without rippling type changes through every consumer.
The four `objc_getClass(...)` calls that previously resolved
NSMutableDictionary / NSNumber at runtime are gone — Phase 3.1's
`__sx_objc_class_init` constructor populates the cached class slot
for each declared `#objc_class` at module load via
`OBJC_CLASSLIST_REFERENCES_<Cls>`.
166/166 example tests; chess clean on macOS + Android via
`tools/verify-step.sh` (iOS sim skipped — no booted simulator in
this run; previous full run was green at HEAD~6).